-LRB- CNN -RRB- -- The medical journal that published a now-retracted paper linking childhood vaccines to autism conducted only a cursory investigation into complaints about the research when they emerged , another British journal reported Tuesday .

The author of the 1998 paper , Dr. Andrew Wakefield , and his co-authors reaffirmed their findings after complaints about Wakefield 's research surfaced in 2004 .

However , the medical journal BMJ reported Tuesday , the examination into how the study was conducted was led by the editor of the Lancet , which published the paper , and involved `` no formal investigation '' of the allegations .

`` In short , the accused were investigating themselves , '' the BMJ reported .

Tuesday 's article is the third and last of a series published by BMJ , which has called Wakefield 's study an `` elaborate fraud '' and accused him of planning to launch a business venture `` off the back of the vaccine scare . ''

Following a three-year investigation , Britain 's General Medical Council ruled in January 2010 that the way Wakefield conducted his research was dishonest and irresponsible . One month later , the Lancet retracted the study . In May 2010 , British authorities revoked Wakefield 's license to practice medicine .

Wakefield continues to insist he has done nothing wrong , and a vocal contingent of advocates for children with autism continues to support him .

In response to the latest article , the Lancet 's editors said they `` strongly disagree '' with the BMJ account `` and firmly stand by our actions and decisions . '' It noted that 10 of Wakefield 's co-authors had their names removed from the paper after learning in 2004 that Wakefield had been paid by lawyers to help build a case against vaccine manufacturers -- a serious conflict of interest he failed to disclose -- and pointed out that Wakefield 's most damning assertion was made at a separate news conference after the study was published , not in the paper that the journal published .

`` From this point forward , Wakefield encouraged the media and a grassroots network of anti-vaccine advocates to believe that this vaccine may cause autism , '' the Lancet said . It added , `` At no point did we actively defend Wakefield 's public statements about the link between MMR and autism . ''

The journal said the Royal Free Hospital , where Wakefield worked at the time of the publication , conducted the 2004 investigation that led to a partial retraction by the paper 's co-authors .

`` At each stage we acted as soon as we had the evidence to do so , '' it said .

Wakefield has accused the author of the BMJ report , freelance journalist Brian Deer , of being paid by the pharmaceutical industry . In financial disclosure forms , Deer has stated that he has received no such payments .

The now-discredited paper panicked many parents and led to a sharp drop in the number of children getting the vaccine that prevents measles , mumps and rubella . Vaccination rates dropped sharply in Britain after its publication , falling as low as 80 % by 2004 . Measles cases have gone up sharply in the ensuing years .

In the United States , more cases of measles were reported in 2008 than in any other year since 1997 , according to the Centers for Disease Control and Prevention . More than 90 % of those infected had not been vaccinated or their vaccination status was unknown , the CDC reported .

CNN 's Miriam Falco contributed to this report .

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`` The accused were investigating themselves , '' a British medical journal reports

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Researcher has denied any wrongdoing , and his theory still has outspoken defenders

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Vaccination rates in Britain dropped sharply after study